Decolorizing material and process of making same



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IDEUOLOBIZHIG MATML AND PROCESS OF MAKING SAME.

Ho Drawing. Application filed June l,

To all chom it may concern:

Be it known that we, HUGH RODMAN, a citizen of the United States, and aresident of ()akmont, Pennsylvania, and EARL E.

BOREN, a citizen of the United States, and a resident of Swissvale, Pennsylvania, have made a new and useful Invention in Decolorizing Material and Process of Making Same, of which the following is a specification.

This invention relates to a'special material having unusual properties as a filtering and decolorizing medium and to the method of producing this material.

In Patent 1,420,754, granted June 27, 1922, to ugh Rodman, one of the joint inventors herein named, a new product is described and claimed, which is produced by heating rotted coal. Rotted coal, as the term is herein employed, refers to the coal in that portion of coal veins which, ordinarily hard and normal, has rotted or deteriorated so that the characteristics of the coal have completely altered. This rotted coal exists near the surface of the ground under which the coal lies, and seems to be due to the slow disintegration of the firm coal, and apparently results in some way from the thin cover over the coal. This rotted coal is a lamina-ted, friable material holding about thirty per cent of water, which produces no smoke or coke when heated (though the coal in the same seam farther back under the hill will both smoke and coke) and which is largely soluble in weak alkalies.

We have discoveredthat when this rotted coal is highly heated, and treated as herein after described, a char is obtained having valuable characteristics in the way of decolorizing oils and other liquids. We have produced a fair decolorizing material by simply assing the raw rottedcoal through a rotary liiln heated to about 1800 degrees Fahrenheit. some care being taken to see 45 that the material was in contact with hot air for at least a short period after most of the volatile matter had been distilled ofl'. We have produced better decolorizing material by first charring the rotted coal and then keeping it in contact with highly superheated steam for a period of time, the duration of which depends upon the relative volume of the steam andthe'char and also upon the fineness of the individual char par- 1918. serial No. 238,162.

ticle. We have also experimented with various other methods of activating this special material and find that it responds to most of them, so that we are convinced the material has special merit. We have passed yarious gases over the rotted coal both during the charring period and after the charringaperiod, and find varying results, but apparently the best results are obtained by passing steam in large amounts over the highly heated char.

The material obtained in this way is a black, highly porous char which, when brought into contact with various liquids, such as oil or brown sugar solution, acts as a vigorous decolorizer and clarifier. lit is much more active than fullers earth or the various decolorizing chars we have been able to secure on the market, clarifying liquids to a greater extent and at the same time permitting of rapid filtration. Apparently there is some special merit in the particular material used, as the same results are by no means obtained from other well known materials when given the same treatment. For example, ordinary coal is practically inert as a 'decolorizing medium when it is sub jected to the treatment described. Ordinary wood charcoal is an extremely poor decolorizing medium, whereas this rotted coal may be made into fairly good decolorizing material (about like fullers earth) by simplv passing it through a kiln.

We have produced thekilned product on a commercial scale, by simply passing the rotted coal slowly through a hot zone in the kiln. And we have made the steam blown material by taking this kilned product and blowing highly superheated steam through it for several hours while it was maintained at about 1800 degrees Fahrenheit in a closed vessel. There is no apparent reason for doubting that this highly valuable product may be manufactured commerciallyby passing rotted coal through a kiln, allowingthe red hot char to drop into a heat insulated chamber and there subjecting it to the action of highly superheated steam. Apparently there is enough fuel value in the volatile matter of the rotted coal to take care of all the heat re uirements enumerated, especially whe it is considered that considerable hot water gas will be generated by the contact of the hot char with the hot swam. The

heat derived from the volatile matter of the rotted coal is suficient to take care of the heat requirements of the kiln. We find that it is generally not worth while to crush the rotted coal prior to kilning it, as it is of afriable nature and breaks up in the kiln so that there are few ieces left larger than an inch in through dimension when the char size and the other conditions-temperature,,

length of contact with the liquid. rate of mixing, etc.,'-being equal. We have also regenerated this material after it had been used for decolorizing, and find it may be brought to approximately its original activ-ity by simply passing it again through a red hot kiln.

It is obvious that where the small amount of ash in the activated char is objectionable, it may be leached out by subjecting the chair to the action of chemical reagents. hydrochloric acid, for example. This will be necessary only in special cases, the ash having no harmful effect in many uses, such, for example, as the clarifying of oils.

While we have described this invention as applying to decolorizing of liquids, it will also be understood that the material may also be used for absorbing gases, and for any of the uses to which ordinary activated char is put.

What we claim is:

1. A filtering and decolorizing material consisting of charred rotted coal which has been subjected to the action of steam.

kiln while subjecting it to a charring tem-' perature, and then subjecting the hot rotted coal to the action of superheated steam.

The method of making decolorizing material, which consists in charring rotted coal, and subjecting thecharred product, unmixed with other material, to the action of superheated steam.

6. The method of making decolorizing material, which consists in charring rotted coal unmixed with other material by slowly passing it through a rotating kiln while subjecting it to a temperature of about 1800 degrees Fahrenheit, and conserving the heat of the charring process by blowing the rotted coal while hot with highly superheated steam.

7. The method of making decolorizing material, which consists in charring rotted coal, by passing it through a rotating kiln 'while subjecting it to a charring'temperature and then subjecting the hot rotted coal to the action of a flow of highly heated=- In testimony whereof, we have hereunto subscribed our names this 31 day of May, 1918.

HUGH ROD-MAN. EARL E. BOREN.

Witnesses:

R. L. KENT, Anna CLoHEnTr. 

